   This implementation of top is lazy, in the sense that it won't proactively
   expire events which are bumped from the top-k set--you have to wait for
   another event with the same host and service to arrive before child streams
-  will know it's expired." 
+  will know it's expired."
   ([k f top-stream]
      (top k f top-stream bit-bucket nil))
   ([k f top-stream bottom-stream]

  as -. = events are passed to children, and - events are ignored.

       A spike           Flapping           Stable changes
  |                 |                    |                    
  |       -         |    -- -   ======   |      =====        
  |                 |        -           |           ========
  |======= ======   |====  -  --         |======              
  +------------->   +---------------->   +------------------>
        time              time                  time


(defn scale
  "Passes on a changed version of each event by multiplying each
   metric with the given scale factor.

  ; Convert bytes to kilobytes
  (scale 1/1024 index)"
  [factor & children]
